Thumbs up on Heater Core Shortcut
I wanted to give a big thumbs up on the heater core shortcut that's posted by the scandanavian 7 series owner. It does indeed work and really makes the job realatively quick and easy... I think I probably still spent 8 hours on it, but I also worked off and on and slow, and cleaned up a bunch of stuff while I was in there and fussed over the placement of the adhesive foam on the core and forgot how things went back together a time or two. If you're quick and focused i would say about 5 hours would be "all" it would take you.
A few notes:
1. Getting at the hose clamp bolts for the feed and return coolant lines on the firewall is a drag. I ended up using a 6mm open end and wished that it ratcheted. I had gone to bavauto and bought their wurth hose clamp wrench in hopes that it would allow me to get at them, but unfortunately they were at too extreme an angle.
2. The coolant line at the far left of the core attaches to the core via a bolt and by rotating a latching collar. This again was in my case a real pain, you might try shaving a tiny amount of the plastic off the back of the core to allow easier engagement of the collar. This may only be a unique circumstance, but it was one of the more frustrating bits of the whole thing.
3. The website mentions the presence of some sort of bar (crash bar?) that extends across the car and which can be unbolted, but hindered access a bit. My 1990 535 did not have this, so i had a totally clear shot at the core.
4. Buy Wurth Heating and Cooling condition spray and use it liberally and also use a rag and clean out the entry to the ducts. The duct that extends directly from the heater box and goes under the console to feed the rear vents was very dirty. I sprayed it out with water and then uses a long handled bird feeder cleaing brush and then hit it with the Wurth.
5. Document which screws go where. Probably common sense, but I have a pretty good memory and thought i could recreate it. Unforutunately 8 hours later i couldn't remember in a few cases which screw was used where.
Tom Der
North Hampton, NH
90 535i
91 M3
05 MCS (Ordered)
